One paradox that is faced in the US is that temperatures reported to the public are most often in degrees F, however,
analysis charts, forecast panels, and Skew-T plots use degrees C. One must readily be able to translate
a Celsius temperatures to a Fahrenheit temperature and vice versa.

One method is to simply use the formula

F = 9/5(C) + 32
C = (F - 32)5/9

Although this method is most accurate, it takes time and requires a calculator. An easier method
is to memorize a few sets of F and C temperatures and interpolate to get an estimate of the
temperature. Memorize the values below:

1. There are ABOUT 2 ° F in one degree C
2. A 10 degree increase on the Celsius scale results in an 18 degree Fahrenheit change

Once the 6 values above or memorized, you only need to interpolate to get an approximate temperature

e.g. What is 17° C? well, 10 is 50 and 20 is 68…. Since there is a 3 degree difference between
17 and 20 on the C scale, then that is a difference of about 6 on the F scale, therefore the
temp is 68 - 6 = 62° F

e.g. What is 83° F? well, 30 is 86…. Since there is a 3 degree F temp change then that
means there is a 1.5 C temp change… therefore the temp is about 28.5 C

2. See the atmosphere is 4-D

The 4 dimensions are length, width, height and time.

*When looking at a composite of analysis charts and forecast panels it is important to put those images
together in your mind and put the atmosphere into motion.
*When looking at a 2-D analysis chart or forecast panel, try to visualize vertical as well as
horizontal synoptic motion.
*Air rarely flows on a perfect horizontal plane, especially in the vicinity
of low pressure cyclones.

4. Understand how the polar jet develops and builds troughs and ridges

a. The jet stream is caused by temperature gradients.
Cold air to the north of the jet has a
much lower thickness than air to the south of the jet. This creates a pressure gradient
force from the warm air toward the cold air. The Coriolis force turns the southerly air
to the right of the path of motion, thus giving the jet stream the typical mid-latitude
west to east motion. See diagram below

b. Troughs and ridges not only build due to the thermal gradients but also because of jet
streaks imbedded within the jet stream flow.

*The molecular weight of water vapor is lighter than that of dry air. Therefore, increasing
the amount of water vapor in the air will cause the air to expand. Diagram below

Just because the temperatures are hot or the dewpoint is high, does NOT mean a location is experiencing
moisture or warm air advection. The average temperature of a layer of air must be increasing or the
average dewpoints in a layer of air must be increasing through time.

If warm air advection or moisture advection occurs at the surface, is will cause air to expand and
thus rise. Therefore, two of the main synoptic scale lifting mechanisms are surface to 700 millibar
warm air advection and moisture advection.